<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>匿名插槽</title>
    <script src="https://unpkg.com/vue"></script>
  </head>
  <body>
   <div id="app">
      <child>
          hello <!-- 不写默认为good,写了就覆盖默认值 -->
      </child>
   </div>
   <script>
     Vue.component('child', {
         template: `
            <button>
                <slot>good</slot>   
            </button>
         `
     })
     new Vue({
       el: '#app',
       data() {
         return {}
       }
     })
   </script>
  </body>
</html>
